Numerous systems for monitoring an analyte amount or concentration in a subject are known in the art, including, but not limited to the following: U.S. Pat, Nos. 5,279,543, 5,362,307, 5,569,186, 5,695,623, 5,713,353, 5,730,714, 5,735,273, 5,771,890, 5,791,344, 5,827,183, 5,840,020, 5,885,211, 5,903,373, 5,954,685, 5,989,409, 5,995,860, 6,022,316, 6,023,629, 6,026,314, 6,044,285, 6,113,537, 6,141,573, 6,142,939, 6,144,869, 6,175,752, 6,180,416, 6,188,648, 6,201,979, 6,233,471, 6,272,364, 6,298,254, 6,299,578, 6,309,351, 6,326,160, 6,360,888, 6,477,395, 6,491,657, 6,512,939, 6,520,326, 6,529,755, 6,560,471, 6,561,978, 6,565,509, 6,576,101, 6,579,690, 6,587,705, and 6,615,078. Many devices used for monitoring of analyte levels in a subject use sensing electrodes. These electrodes are typically produced by thick film deposition of an ink material.
The ink material may comprise graphite as a conducting material, a polymer binding material, and an organic solvent. Ink material may further comprise platinum black and/or platinum-on-carbon as the catalyst. U.S. Pat. No. 6,042,751 pertains to a conductor composition of up to 5% platinum powders and/or platinum deposited on graphite, modified graphite and a thermoplastic polymer such as the styrene-containing acrylic copolymers poly(styrene-acrylonitrile). U.S. Pat. No. 6,309,535 pertains to an electrode consisting of graphite particles coated with a transition metal catalyst, carbon particles, and a binder that is a vinyl chloride/vinyl acetate copolymer.
U.S. Pat. No. 5,928,571 discloses a conductive composition for iontophoretic electrodes containing silver particles, silver chloride particles, carbon and graphite as the conducting material, and a copolymer of hydrophilic and hydrophobic monomers. The hydrophobic monomers can be styrene, and the hydrophilic monomers can be acrylates.
EP 0 942 278 B1 discloses a sampling system for monitoring the concentration of an analyte present in a biological system, comprising a sensor element in operative contact with a reservoir, wherein the sensor element reacts electrochemically with hydrogen peroxide produced in the reservoir to provide a detectable signal, characterised in that the sensor element comprises an electrode having a geometric surface area which ranges from 0.1 to 3 cm2, a background current which ranges from 2 to 60 nanoamps (nA) or less when measured in a buffer solution at 0.6V, and a sensitivity which ranges from 6 to 180 nA/μM of hydrogen peroxide when measured in a buffer solution at 0.6V.
The present invention provides methods and compositions for improving performance of analyte monitoring systems that employ sensing electrodes comprising the conductive compositions of the present invention.